This paper introduces the field application of FMS-1 fixed optical fiber connectors to tour single mode optical cable lines 154 have been used
the average connecting loss is 0.125dB and the average joint loss for each optical fiber line is 0.15dB. The longest connected line is 33km. The return loss of all applied connectors from Qingyang to Ji uhuashan has been measured and results show that it is more than 38dB.